More than 4,600 sign letter protesting against death of Cambridge PhD student and demanding investigation into forced disappearance in Egypt

More than 4,600 academics from across the globe have signed an open letter protesting against the death of Giulio Regeni, a Cambridge PhD student from Italy whose body was found on the outskirts of Cairo bearing signs of torture last week, and demanding an investigation into the growing number of forced disappearances in Egypt.

The letter, published by the Guardian, has attracted signatories from more than 90 different countries and across a wide range of academic disciplines. It is likely to heap further pressure on both the Egyptian and Italian authorities to uncover and make public the facts behind Regeni’s killing.

The 28-year-old, who was researching labour unrest and independent trade unions – a politically-sensitive topic in Egypt – went missing on 25 January, the fifth anniversary of the start of Egypt’s revolution, amid an unprecedented security crackdown.

His body was discovered nine days later by the side of a road, marked with cigarette burns, bruising and multiple stab wounds. The Italian interior minister, Angelino Alfano, said that Regeni had been subjected to “inhuman, animal-like violence”.

The Italian foreign minister, Paolo Gentiloni, said in an interview with La Repubblica published on Monday that Egypt appeared to be cooperating with a team of Italian investigators dispatched to Cairo but warned Rome wanted justice for Regeni. “We will not settle for alleged truths,” he said. “We want those really responsible identified and punished on the basis of law.”

It has since emerged that Regeni wrote occasional reports from Egypt under a pseudonym for the leftwing Italian newspaper Il Manifesto. In a piece published posthumously under Regeni’s own name, he criticised the scale of authoritarianism and repression under President Abdel Fatah el-Sisi and hailed “popular and spontaneous initiatives that break the wall of fear”.

Italian media outlets have pointed the finger of suspicion over Regeni’s fate at Egypt’s security forces.

The Egyptian interior minister, Magdy Abdel Ghaffar, described charges of security forces involvement as “completely unacceptable” when asked at a press conference on Monday if Regeni had been arrested by police. “This is not Egyptian security policy; Egyptian security has never been accused of such a matter,” he said.

The letter notes that, according to human rights organisations, state institutions in Egypt “routinely practise the same kinds of torture that Giulio is reported to have suffered against hundreds of Egyptian citizens each year”. It calls for an independent investigation into Regeni’s death and “all instances of forced disappearances, cases of torture and deaths in detention during January and February 2016 … in order that those responsible for these crimes can be identified and brought to justice.”

Several hundred professors and other senior academics have put their name to the letter, including Charles Butterworth, emeritus professor of political philosophy at the University of Maryland, Sir Timothy Gowers, Royal Society research professor of mathematics at the University of Cambridge, and Ha-Joon Chang – the economist and bestselling author of '23 Things They Don’t Tell You About Capitalism'.

It was begun by Regeni’s colleagues at Cambridge and subsequently went viral among academics.

The number of forced disappearances has risen sharply in Egypt over the past year, coinciding with the state’s growing intolerance of any form of political opposition or dissent.

“National human rights groups are reporting an average of three people a day being forcibly disappeared across the country,” said Mohamed Elmessiry, Egypt researcher at Amnesty International.

“Both the security forces and the judiciary have failed to hold officers to account in cases where citizens have been tortured to death, or which involve excessive use of force.”

The Egyptian government was invited to comment but provided no response by the time of publication.